Physics
posted by Jen on .
A 125 kg fullback is running at 5.0 m/s to the east and is stopped in 0.75 s by a headon tackle by a tackler running due west.
a) Calculate the original momentum of the fullback.
i did this and got 625 kg m/s
b) Calculate the impulse exerted on the fullback
i did this and got 625
(c) Calculate the impulse exerted on the tackler.
I did this and got 625 but D I CANT FIGURE OUT !!!
(d) Calculate the average force exerted on the tackler.

d) force*time=changeinmomentum
since you don't have time of impact, you cant do it.
other answers: momentum and impulse are vectors, you didn't indicate direction. 
Since the unit for force, a newton is equal to kg*m/s^2 you must divide the momentum, kg*m/s of the player by the time it took for him to be tackled.